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1.
The pollination process and breeding system of the sympatric Habenaria johannensis, H. macronectar, H. megapotamensis and H. montevidensis was documented for native populations from Rio Grande do Sul, Brazil. All species investigated offer a nectar reward (mean values of total sugars ranging from 18 to 26%) concealed in a spur. Habenaria montevidensis is pollinated by butterflies (Hesperiidae, especially of the genus Urbanus) that carry pollinaria on their eyes; the other three species are pollinated by Sphingidae. Habenaria johannensis is pollinated by the moths Manduca rustica and M. sexta that carry the pollinaria at the base of the proboscis. Habenaria macronectar is pollinated by the moths Eumorpha labrusca and M. cf. lucetius, and these bear pollinaria between the palpi. Habenaria megapotamensis is pollinated by moths of M. cf. lucetius that bear the pollinaria on the proboscis. All species studied are self‐compatible, but pollinator dependent. They also displayed high reproductive success (ranging from 69.48 to 97.40%) and male efficiency factors slightly higher than 1, suggesting that at least one flower was pollinated for each flower acting as pollen donor. At the study sites, the investigated Habenaria spp. are isolated (in terms of pollination) by a set of factors that includes differing floral morphologies, different pollinators and/or different pollinarium placement on the pollinator. © 2012 The Linnean Society of London, Botanical Journal of the Linnean Society, 2012, ??, ??–??.  相似文献   

2.
A new species in the previously monotypic, endemic New Caledonian genus Gastrolepis (Stemonuraceae) is described. Gastrolepis alticola differs from G. austrocaledonica by its shorter and thicker petioles, strongly coriaceous leaves with revolute margins, shorter inflorescences, and pubescent corollas. The new species is further distinguished by its ecology, occurring only in high‐altitude maquis on two massifs in southern New Caledonia, Mt. Kouakoué and the Montagne des Sources. Gastrolepis alticola is assigned a preliminary conservation status of ‘Endangered’ using the World Conservation Union (IUCN) Red List criteria. Comparison of the IUCN threat status for the 19 species endemic to this distinctive, restricted vegetation type reveals a striking lack of consistency and underscores the need for a reassessment of the entire New Caledonian flora. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 157 , 775–783.  相似文献   

3.
Lichens are the dominant organisms on most of the South Atlantic island of St Helena. In total, 220 different species were found during a recent survey, most of which have never been reported from the island. Previously, less than 50 lichen species were reported from the island, one half of which are most probably incorrect records. The total number of lichens known from the island now stands at 225. Most species could be identified, but the following, most probably endemic, species are described as new to science: Dolichocarpus seawardii , which is only the second species in this genus, the type being from Chile; Dermatiscum pusillum , which is only the third species in this African genus; Dimelaena triseptata ; Xanthoparmelia beccae ; and four Ramalina species, Ramalina geniculatella , R. ketner‐oostrae , R. rigidella , and R. sanctae‐helenae . The lichen flora has many species in common with that of the geologically much younger Ascension Island, where just under 100 species were recently found by the author, most of which are equally new to that island. Lecanora sanctae‐helenae, previously known as the only endemic lichen of St Helena, was also found to be abundant on Ascension Island. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 158 , 147–171.  相似文献   

4.
We investigated the pollination of Habenaria tridactylites, an endemic orchid of the Canary Islands. The entirely green, widely open flowers have a long spur containing nectar. We carried out fieldwork, a molecular clock analysis, herbarium surveys, identified pollinators by both morphology and DNA barcoding, and measured the length of floral spurs and insect tongues using a combination of traditional and innovative micro‐CT scanning methods to 1) determine the pollinator of this orchid and 2) investigate correlations between local mean spur length and age, altitude and longitude of the island. Habenaria tridactylites was found to be pollinated on Tenerife by both small and intermediate sized moth species with variable tongue lengths and mostly belonging to Geometridae and to a lesser extent Crambidae, Erebidae, Noctuidae and Tortricidae. Of the sixteen moth species identified, nine are endemic to the Canary Islands or Macaronesia. The different local populations of H. tridactylites on the islands of Gran Canaria, El Hierro, La Gomera, La Palma and Tenerife with different ages and distances from mainland Africa, did not show a significant correlation of mean spur length and altitude, but did show a significant and positive linear correlation with longitude and the geological age of the island. The latter is congruent with the evolutionary arms race theory first proposed by Darwin, suggesting that flowers gradually evolve longer spurs and pollinators longer tongues.  相似文献   

5.
Two new species of Hedysarum, H. alii Haidar Ali & Qaiser sp. nov. and H. shahjinalense Haidar Ali & Qaiser sp. nov. are described from Chitral in Pakistan. As far as known, both new species are endemic to Chitral and are categorized as ‘Critically Endangered’ (CR). In addition, three other species of Hedysarum are recorded from Pakistan for the first time, viz. H. volkii Rech. f., H. brahuicum Boiss. and H. sericeum M. Bieb. These are also ‘Critically Endangered’ (CR) at a national level. A key to all 12 species of Hedysarum occurring in Pakistan is provided.  相似文献   

6.
Summary  Two new species, Habenaria ciliatisepala and H. egleriana (Orchidaceae, Orchideae), from the cerrado of central Brazil and campo rupestre of the Espinha?o mountain range in Minas Gerais and Bahia, are described and illustrated.  相似文献   

7.
We examined the comparative phylogeography of all species within the endemic New Zealand skink genus Cyclodina to gain insight into the influence of historical processes on the biogeography of the North Island fauna. Until 1–2 kya, six Cyclodina species occurred sympatrically across the North Island of New Zealand. However, most species have undergone dramatic distributional declines subsequent to the introduction of mammals and the arrival of humans. We compare the phylogeographic patterns evident in Cyclodina species in three biogeographic categories: widespread species (Cyclodina aenea, Cyclodina ornata), North Island disjunct relics (Cyclodina macgregori, Cyclodina whitakeri), and northeastern island relics (Cyclodina alani, Cyclodina oliveri, Cyclodina townsi). Mitochondrial DNA (ND2) sequence data was obtained from across the entire range of each Cyclodina species. We used Neighbour‐joining, maximum likelihood and Bayesian methods to examine the phylogeographic patterns present in each species. Phylogeographic patterns varied among species in different biogeographic categories. Substantial phylogeographic structure was evident in the two widespread species (C. aenea, C. ornata), with Pliocene and Pleistocene divergences between clades evident. Divergences among island groups in the three northeastern island relic species (C. alani, C. oliveri, C. townsi) occurred during the late Pliocene–Pleistocene. By contrast, relatively shallow structure, indicative of late Pleistocene divergences, was present in the two North Island disjunct species (C. macgregori, C. whitakeri). The results strongly suggest that the Poor Knights Islands population of C. ornata represents a new species. We suggest that the contrasting phylogeographic patterns exhibited by Cyclodina species in different biogeographic categories might be related to body size, ecology, and habitat preferences. © 2008 The Linnean Society of London, Biological Journal of the Linnean Society, 2008, 95 , 388–408.  相似文献   

8.
Preliminary checklist of the orchids of Chile   总被引:1,自引:0,他引:1  
This article provides a preliminary checklist of the orchids occurring in Chile, based on historical and recently published literature. Data compilation was assisted by using databases available on the Web (IPNI, W3Tropicos and KR). The list comprises seven genera ( Aa , Bipinnula , Brachystele , Chloraea , Codonorchis , Gavilea and Habenaria ) and 50 taxa (49 species and one variety), 25 of which are believed to be endemic to Chile. It includes the publication of a new combination, Gavilea feuilleana comb. nov.   © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 143 , 449−451.  相似文献   

9.
10.
Trophic networks in small isolated islands are in a fragile balance, and their disturbance can easily contribute toward the extinction vortex of species. Here, we show, in a small Atlantic island (Raso) in the Cabo Verde Archipelago, using DNA metabarcoding, the extent of trophic dependence of the Endangered giant wall gecko Tarentola gigas on endemic populations of vertebrates, including one of the rarest bird species of the world, the Critically Endangered Raso lark Alauda razae. We found that the Raso lark (27%), Iago sparrow Passer iagoensis (12%), Bulwer's petrel Bulweria bulwerii (15%), and the Cabo Verde shearwater Calonectris edwardsii (10%) are the most frequent vertebrate signatures found in the feces of the giant wall gecko. This work provides the first integrative assessment of their trophic links, an important issue to be considered for the long‐term conservation of these small and isolated island ecosystems.  相似文献   

11.
Three new species of Habenaria (Orchidaceae) section Nudae from Rio Grande do Sul, southern Brazil, are described and illustrated: Habenaria australis, H. kleinii and H. sobraliana. These are the first records of H. sect. Nudae for the state. Based on the examination of living and dried specimens, a total of 33 species and 400 collections of Habenaria were recorded for Rio Grande do Sul. Based on this survey, an updated checklist of the genus Habenaria for Rio Grande do Sul has been compiled. Four species are known only from this state, while seven other species are restricted to southern Brazil, Argentina and Uruguay. Habenaria hieronymi, previously known only from Argentina, is recorded for the first time from Brazil, and H. brachyphyton, H. ekmaniana and H. melanopoda are new records for Rio Grande do Sul.  相似文献   

12.
Ricefishes, known best by the model organism, the medaka, Oryzias latipes Temminck & Schlegel, 1846, comprise the family Adrianichthyidae, which ranges broadly throughout fresh and brackish waters of Central, South and Southeast Asia and the Indo‐Malay‐Philippines Archipelago as far east as Timor. Twenty‐eight Recent species are recognized here in two monophyletic genera, Adrianichthys and Oryzias. Xenopoecilus and Horaichthys are placed in synonymy of Oryzias for the first time. Adrianichthys comprises four species from Lake Poso, Sulawesi, Indonesia. Oryzias comprises 24 species that live throughout the range of the family. A fossil genus and species, ?Lithopoecilus brouweri from the Miocene of central Sulawesi, is included tentatively in the Adrianichthyidae. Evidence for the sister group relationship of adrianichthyids and exocoetoids is reviewed briefly and that relationship corroborated. Monophyly of adrianichthyids is likewise strongly supported here. Species groups within Oryzias are diagnosed as monophyletic largely based on osteology, colour pattern and meristic variation. They correspond only in part to species groups previously recognized based on chromosome constitution. Miniature species do not comprise a monophyletic group; disjunct absolute size in close relatives has evolved repeatedly. Oryzias latipes is a member of a species complex that includes O. luzonensis, O. curvinotus and the miniatures O. sinensis and O. mekongensis. A new species, Oryzias bonneorum sp. nov. , is described from Lake Lindu, Sulawesi, Indonesia. Lectotypes are designated for Haplochilus celebensis Weber, 1894 and Haplochilus timorensis Weber & de Beaufort, 1922. No claim to original US Government works. Journal compilation © 2008 The Linnean Society of London, Zoological Journal of the Linnean Society, 2008, 154 , 494–610.  相似文献   

13.
Halocnemum yurdakulolii Yaprak is described as the second species of the previously monotypic genus Halocnemum. The species is endemic to the Göksu Delta in southern Turkey. The main morphological characteristics that separate H. yurdakulolii from H. strobilaceum (Pall.) M.Bieb. are growth form and spike morphology. Apart from these morphological differences, the species show a clear genetic differentiation. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 158 , 716–721.  相似文献   

14.
To examine the diverse colonization histories in eight tiger beetle species of the genus Cylindera (Coleoptera: Cicindelidae) on the East Asian islands, we conducted phylogenetic analyses and divergence time estimation using mitochondrial cytochome oxidase subunit I (COI) and nuclear 28S rDNA sequences. The island fauna consisted of four subgenera: Apterodela, Cicindina, Ifasina, and Cylindera. Apterodela is a flightless group with large bodies, whereas the others are fliers with small bodies. In Apterodela, the divergence among endemic species in Taiwan, Japan, and the mainland was ancient (2.1–4.7 Mya), as expected from their flightlessness. Their dispersal might have occurred across the extended landmass in East Asia during the Pliocene. In the subgenus Cicindina, Cylindera elisae has spread throughout East Asia, from which an endemic species, Cylindera bonina, was derived on the oceanic Bonin Islands during the early Pleistocene (0.9 Mya). This indicates the significance of Cylindera bonina, which is currently confined to a single island, for conservation. In the subgenus Ifasina, Cylindera kaleea is widely distributed in East Asia, and its sister species Cylindera humerula, endemic to Okinawa Island, diverged 1.0 Mya, whereas Cylindera psilica on Taiwan and the Yaeyama Islands diverged approximately 0.8 Mya. In the subgenus Cylindera, the colonization of Cylindera gracilis in Japan from the mainland occurred during the last glacial period. With the exception of C. bonina, which likely colonized new territories by flight or drifting, other dispersal events might have used land connections that occurred repeatedly during the Pliocene and Pleistocene. © 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2011, 102 , 715–727.  相似文献   

15.
16.
Calathea dorothyae J. M. A. Braga & H. Kenn. sp. nov. from the sandy coastal plains of southeastern Brazil is described and illustrated. It is apparently endemic to the ‘Cabo Frio Center of Plant Diversity’, and it is considered ‘Critically Endangered’ (CR). The new species is somewhat similar to C. reginae J. M. A. Braga and C. sphaerocephala K. Schum. with which it is compared.  相似文献   

17.
Greece is characterized by high plant diversity (5800 species) and endemism (15.6%). This study attempts a first overall assessment of the taxonomy, distribution, traits and conservation status of the Greek endemic plants. The endemic species belong to 56 families and 242 genera. Most of the endemic plants have a narrow geographical and altitudinal distribution range. The southern floristic regions are richer in endemic species. The species area relationships for endemics (EARs) for island and continental floristic regions explain over 50% of the variation in number of species and are characterized by steep curves. Analysis of the distributional pattern of the endemics by similarity coefficients offers useful insights into the palaeogeography and biogeography of Greece. The endemic species occur at all altitudes, but the altitudinal distribution shows a predominance of local endemics at 0–600 m in the island regions and in higher zones in the continental regions. The life form spectra show a predominance of hemicryptophytes and chamaephytes. This trait seems indicative of their habitat and adaptive strategy and may be related to speciation processes. The overview of the conservation status of the Greek endemics indicates that over 40% of the taxa are threatened or near threatened. © 2010 The Linnean Society of London, Botanical Journal of the Linnean Society, 2010, 162 , 130–422.  相似文献   

18.
The Mentawai and Batu Island groups off the west coast of Sumatra have a complicated geological and biogeographical history. The Batu Islands have shared a connection with the Sumatran ‘mainland’ during periods of lowered sea level, whereas the Mentawai Islands, despite being a similar distance from Sumatra, have remained isolated from Sumatra, and probably from the Batu Islands as well. These contrasting historical relationships to Sumatra have influenced the compositions of the respective mammalian faunas of these island groups. Treeshrews (Scandentia, Tupaiidae) from these islands have, at various times in their history, been recognized as geographically circumscribed populations of a broadly distributed Tupaia glis, subspecies, or distinct species. We used multivariate analyses of measurements from the skull and hands to compare the island populations from Siberut (Mentawai Islands) and Tanahbala (Batu Islands) with the geographically adjacent species from the southern Mentawai Islands (T. chrysogaster) and Sumatra (T. ferruginea). Results from both the skull and manus of the Siberut population show that it is most similar to T. chrysogaster, whereas the Tanahbala population is more similar to T. ferruginea, confirming predictions based on island history. These results are further corroborated by mammae counts. Based on these lines of evidence, we include the Siberut population in T. chrysogaster and the Tanahbala population in T. ferruginea. Our conclusions expand the known distributions of both the Mentawai and Sumatran species. The larger geographical range of the endangered T. chrysogaster has conservation implications for this Mentawai endemic, so populations and habitat should be re‐evaluated on each of the islands it inhabits. However, until such a re‐evaluation is conducted, we recommend that the IUCN Red List status of this species be changed from ‘Endangered’ to ‘Data Deficient’. Published 2013. This article is a U.S. Government work and is in the public domain in the USA, Biological Journal of the Linnean Society, 2014, 111 , 290–304.  相似文献   

19.
Kosteletzkya s.s. is a genus of 17 species (excluding the endemic species of Madagascar), found in the New World, continental Africa, Madagascar, and Southeast Asia. Recent chromosome counts revealed diploid, tetraploid, and hexaploid species. To estimate the history of the genus, we sequenced nuclear and plastid loci for nearly all Kosteletzkya spp., in the majority of cases, with multiple accessions per species. The African species form a paraphyletic grade relative to a New World clade. Polyploidy has occurred only in some African species, resulting in the relatively ancient formation of one putative autotetraploid species (K. semota), one recent allotetraploid species (K. borkouana), two relatively ancient allotetraploid species (K. begoniifolia and K. rotundalata) and one recent allohexaploid species (K. racemosa). Our inferences regarding the hypothesized parentage of the polyploids mostly corroborate previous work based on chromosome‐pairing patterns in artificial hybrids, highlighting the utility of these complementary data sources. © 2015 The Linnean Society of London, Botanical Journal of the Linnean Society, 2015, 179 , 421–435.  相似文献   

20.
Recent revision of the fern diversity of the French Caribbean island of Guadeloupe and its dependencies (Marie Galante, Les Saintes and La Désirade) resulted in the listing of 292 native ferns and club mosses in 28 families and 88 genera, of which eight ferns are endemic to Guadeloupe and 20 taxa are only recorded from the Lesser Antilles. Additionally, 21 species have recently been found to be naturalized. Nineteen new combinations are made and a new hybrid is described. Many types from the Fée collection have been reassessed and a number of names are lecto‐ or neotypified. Studied specimens are cited and localities are provided. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 161 , 213–277.  相似文献   

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